Patent · US Expired

Method for fabricating graded LDD transistor using controlled polysilicon gate profile

US6287922A · kind A · utility

13Cited by
3References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 28, 1998
Grant dateSep 11, 2001
Priority date
Expiry dateSep 28, 2018

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S438/978
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

An ultra-large scale CMOS integrated circuit semiconductor device with LDD structures having gradual doping profiles and reduced process complexity is manufactured by forming a gate oxide layer over the semiconductor substrate; forming a polysilicon layer over the gate oxide layer, forming a first mask layer over the polysilicon layer; patterning and etching the first mask layer to form a first gate mask; anisotropically etching the polysilicon layer to form a first polysilicon gate, wherein the first polysilicon gate has sidewalls with sloped profiles, and implanting the semiconductor substrate with a dopant to penetrate portions of the sidewalls to form one or more graded shallow junctions with gradual doping profiles.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.